Mold for a plastic ring having an annulus and a motif



' Nov. 7,' 1950 w. M. LESTER Y 2,529,091

' MOLD FOR A P STIC RING HAVING AN NU DA IF' ed0c.5,19

M/ L /A/u M L55 TER (Ittorneg Patented Nov. 7, 195.0

" UNITED STATES -Monnron A'rLAsTIC anno AN n ANNDLUSANDAMQTHT' y l Wiuiamliimeser.minimum:.il

Application entonces, 194s,.seria1-N;-'z01,446

weet.-

'Ifhe invention herein disclosed relates-,to the molding of thermo-plastic ,frnateri'al :and more particularly to a die for molding .a`,r ing having an annulus and a motif. v A In the manufacture of `rings from thermo, plastic materia1, such as finger rings, for ;.ex ample, :that consist of an annulus and a motif, it has been the practice, prior to this invention, to mold the annulus and motif sepa'rate l y.'` II lhe two .parts are-then secured together with-.cement Another object of the inventionis Vyizcyprpvide a die for molding athermo-plalstic ringhaving an annulus and .a motif, inasingle. piece...,A

further object ofthe ginventionis t .proifi'dera die forthe vpurpose mentioned that isg'sirnpl in construction and in .which the motifvcay'ity may be changed withoutthe :necessity of making Qan entire neW die The foregoingobjectsand certain advantages that will hereinafter appear are realized .in tthe dies .and the ring illustrated in the accompanying drawing and described in detail below, frforn which description a. clearer understanding ofthe invention may he had.

The drawings include: I Fig. 1 which is a fragmentary, sectional ,plan of a. die in the .closed position thereof; Fig. 2 which is a like, fragmentary, sectional plan of the same in the vopen position thereof;

Fig. 3 which -is a fragmentary, sectional plan o of a modified die .in the closed position thereof.;

Fig. 4 which is' a like, fragmentary, sectional plan of the same in the open position thereof;

Eig. 5 which is a fragmentary, .sectional .plan of another modification of the die in the closed position thereof; l

.Fig 't5-which isa like, fragmentarygsectional plan of .the same in the open position thereof;

Fig. 7 which is a plan of a ring comprehended within the invention; and

.,Fig. 8 which is an elevation of thesame..`

'The ring illustrated in Figs. .7 .and 8 of the drawing and shown in certainof the other figures consists of a single piece of molded, thermoplastic material. :ilanda motif 2. 'Ihe motif, which maybe of any desired design, is .wider and longer 'than vthe thickness :ofthe annulusd. The ring .is.molded as 'a singlefzpiece of thermo-plastic material .in ajthree part die such as .any one .of the `.dies illustrated irl-Figs. lto 6.. :v I l The die.,of Figs. .1 .and 2 .includes an xinjection half oiaparti `and anejectorzh'alfor prt'- l. AS is common and Well known in the art, the injection part of the die is mounted stationary on This ring includes an annulus y the eeeten-melding @neckline -'I'he.'.eiecter half ef. fthe melsieeridie is mevsltedenthe mcvablefdie holder of the machine tandis vmoved toward and ewayfimm 11e injection halfto close and Open the Y@illu -1 d Y y, In therdie illustrated inEigs. 1. and-A2, :the fin- -iectien halfrS.; of` the diezzihas Ea cavity .i @formed therein :complementary to .the ydesired shape ont .suohfasthe lmotif 2. lThis cavity .fori (theA` motif ',vholly. Within the injeotion-flalf of-:thedieandl` terminates ina :dat slmface a'tfth .planefof ftheiflpartin'g' line of lthe two :halves -of 4xthe .die. "1f'iI'hat is` to say, the surrace of `.the ejector f'halvfr of A:the die' 'closes the oavityfor'themtif; I: Y 'eie'tc rfhalffoffthe1 vdie has'a recess 6 rqrmeuthegieand which awo ldie -pa'rts vI cada arlisngably n i'p'untea. :The side 'iwaus -9 "and "510' 'offthe ireies's -are inclined to a central praaggga1ie1jacythe=1ne pf increment d; the Qeot; half fthev'die Y'o lngl5"com rverge'. -The die caisses ennemie.. tremblemen- -tary t o v 'dferiga'gingth' ,clined'vvall 9vfo'f the re'ee'ssffs; anda straight suface l2 pafa'ueito a vertical Yplane gintaininug the line of movement cf the eiectorha1f-efheldie I nlikemanner., Athe die partlhasaiij inclined A surface I3 com:- plementary. to and engaging the inclined wall i113 of the recess and .a straight surface 'I4 enpcsedtg thesireghslfce 1.2.20.f thefdie part Il.. "IheI inclined Surfac' .il ef thgpart 1 4isheld ,in 'engagement .with Lille. Surface 9 by .a "ein" .5 rextendingA intogarielongated. inclined slot L6 the partfi'l; i vsimilar.pin Il .extends into an .e10ngata,.,inclined SlotJj in -thefpart r8.. .The

vents ,Lparjiaim are param; to the walls .9 and il-e'iiec-iitel i i l of ,the 1 and .8 vcontain a. .part -effth'eeevitvfferilieaeeulve; Qeipert lwrthe annuluscavityfisgformed;inthe-surface (l2 ofthe nari-1. .adjacent .theend thereof. i'lheether pari .2..0 ef.-:the.-ennuluicevity is.,.fer.med.infthef.sur.face 11?. ci :the peri-a6.. adieeeettheend-thereef-- fIt .te nefalctedfihat :the .annulus cavity cuts :throueh the end sm'faees 5l-I `and 1.22 of the parts V'I vand-8 respectively. u..

11.1 athefclosedaposition'of. the die (Fig. l), the cavitiesgt and'20 form anlannlar cavity'fwhih :through thesurfaces :2 Iand.22.communicate with fthe motif fcanityi :in-.the 'injector -halfiof fthe .die JhuaA a lmoldrcavity is.:forrned `which-s. comple.- mentary to a ring, a finger ringfforcexamplefthat includes a motif and an annulus. Into this cavity through a gate (not shown) thermo-plastic material is injected to form a ring, such as the ring shown in Figs. 7 and 8.

After the mold cavity has been filled and the thermo-plastic solidified therein, the ejector half 4 of the die is moved away from the injection half 3. The motif 2 moves with the ejector half out of the cavity 5. When the ejector half 4 of the die has moved a predetermined distance away from the injection half, the parts 1 and 8 are engaged by stationary ejector pins 23 and 24 respectively, Which extend through openings in the ejector half of the die. Upon further movement of the ejector half of the die, the ejector pins hold the parts 1 and 8 stationary and the pins I5 and l1, acting in the slots I and I8 respectively cause the parts 1 and 8 to separate, as shown in Fig. 2. The ring is thus free to drop, or be removed from the die. As the ejector half moves to the closed position, the ,parts 1 and 8, by contact with the surface ofthe injection half 3, are caused to move into thev recess-6, and by virtue of theinc'line'd surfaces 9 and Il, and l0 and i3, the 'die partsare moved together.

1 In the die illustrated in Figs. 3 and 4, the cavity 25 for the motif is formed in a sliding core 26 that is moved at right angles to the relatve 4movement of the injection half or part 21 and he ejector half or part 28. The injection half 21 is cut away at 29 and the injector half is cutaway at; 30, so that4 in the closed position-of the die, a recess is formed in the-die for the sliding core. The cavity 3,0, for theannulus is formed in part inthe injection half 21 and in part in the ejector half 28. Each part of the annulus cavity extends through the surfaces 3| and 32 rof the injection half 21 andv the 'ejector half 28 respectively, which contact the end surface of the core 26 in the .closed position of the die. Thus in the ,closed position of the die, the motif cavity 25 and .the annulus cavity communicate and form a cavity that is complementary to a` ring. When the fdiefisopened, the core 26 slides at right angles todthe'linebf movement ofl the ejector half 28. :The iinglformed may drop vor be otherwise refmovdfioin the die.

' YTwosliding coresor die parts 33 and 34 are utilized inthe die illustrated in Figs. 5 and 6. In this die, the motif cavity is formed in the surface 36 o f theV injection half 31 of the die. The ejector half 38 `of the die has a plane surface and the sliding cores 33 and 34 move between the injection and ejector halves of the die at right angles to the line of movement of the ejector h'alf. A part 39 o'f the annulus cavity 40 is formed inthe end surface of the core 33 and the other part`4l of the annulus cavity is formed in the end surface of the core 34. These cores are moved toward and away from each other in a manner well known'in the art to bring the end surfaces together and to separate them. The tpart39 of the annulus cavity extends through the side wall 42 of the core 33, and the part 4Il extends through the side wall 43 of the core 34. In theclosedposition of the die -(Fig. 5), the end surfaces of the cores are in contact and centered with respect to the motif cavity 35. Thus, a single cavity is formed complementary to a nger ring having a motif and an annulus. When the ejector half of the die moves away from the injection half, the cores slide to separate the end surfaces thereof. The die is thusopened and the ring formed may drop, or be removed from the die as is evident from Fig. 6.

Aring made as above described and consisting of a single piece of molded, thermo-plastic material has many advantages. It is comparatively inexpensive since no assembly operations are required, and it is superior in appearance. This latter is particularly true when the ring is made from a transparent or translucent plastic because there is no joint between the annulus and the motif to detract from the appearance of the ring.

A die embodying the invention, such as the dies illustrated in the drawing and described above, is readily made because of the simplicity of the construction. In addition, for a given size ring, the motif may be changed by merely changing the die part containing the motif cavity. Alternatively, different sized rings may be made with the same motif by changing the die parts in which the annulus cavity is formed. These are important advantages as such rings are novelties, made in several sizes and'with a great variety of motifs.

It will be obvious that various changes may be made by those skilled in the art in the dies and the ring illustrated in the drawing and described in detail above within the principle and scope of the invention as expressed in the appended claims.

I claim:

1. A die for molding a ring having an annulus and a motif from thermo-plastic material which die consists of a plurality of separable parts, each part having a portion ofthe mold cavity therein and including two partsrelatively movable at right angles to the plane of the annulus cavity, and a third part having the cavity for the motif therein, and means for effecting relative movement between said first mentioned two parts and said third part parallel to the plane of the annulus, the relative separating movement of said three parts being such that a ring molded in the cavity may drop from the mold.

2. A die for molding a ring having an annulus vand a motif from thermo-plastic material REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number. Name Date 488,570 Miller Dec. 27, 1892 548,895 Staples Oct. 29, 1895 2,003,376 Lesmeister June 4, 1935 2,038,205 Case Apr. 21, 1936 2,156,459' Mucher May 2, 1939 2,330,762 Tooker Sept. 28, 1943 2,358,857 Gits Sept. 26, 1944 2,367,962

Reibold et al. Jan; 23, 1945 

